The other disorders discussed here include a variety of cranio-facial pain disorders or cephalic neuralgias.

They are often named according to the nerve responsible for the pain. Examples discussed in this section are cluster headache (also known as petrosal neuralgia or migrainous neuralgia), geniculate neuralgia (GN), sphenopalatine neuralgia (Sluder's neuralgia), paratrigeminal neuralgia of Raeder, and occipital neuralgia.

Other facial pain disorders include anaesthesia dolorosa and atypical facial pain. Other cranial nerve disorders include balance difficulty or dizziness (vertigo) and ringing in the ears (tinnitus).

Migrainous Neuralgia (Cluster Headache)

Cluster headache is characterized by severe pain on one side of the face in the frontal and/or eye (retro-orbital) regions. The pain, described as stabbing or shooting, lasts anywhere from a few minutes to hours, and may awaken sufferers from sleep. These attacks are usually "clustered" over several days to weeks and are followed by remissions lasting weeks to months. Men are more often affected than women (at a ratio of 8:1), and the usual age of onset is in the 20's or 30's.

Associated symptoms include involvement of the autonomic system. During or following an attack, sufferers may experience tearing, nasal stuffiness or running, facial swelling or flushing, and eyelid edema, all on the affected side.

A diagnosis of cluster headache is based on clinical symptoms combined with normal findings in radiological and laboratory tests, including CT and MRI scans.

Other names for cluster headache include migrainous neuralgia, petrosal neuralgia, Horton's histamine cephalgia, red migraine, erythromelalgia of the head, and paroxysmal nocturnal cephalgia. About one-fifth of sufferers develop daily and relentless symptoms in a condition known as chronic cluster headache. A rare variation of the disease includes symptoms of trigeminal neuralgia in what is termed cluster-tic syndrome.

Treatments: In the majority of sufferers, medical therapy is the most effective treatment for cluster headache. The mainstays of medical treatment include methysergid, Ergotamine, Verapamil, Flunarizine, valproic acid, and lithium carbonate. Corticosteroids, including Prednisone, can also control cluster headache and generally take effect within a few days. Treatment of newly diagnosed cluster headache may be initiated with a prescription of subcutaneous Sumatriptine. Oxygen may also be used to control acute attacks of pain and is effective in two-thirds of sufferers.

However, approximately one-tenth of sufferers develop intolerable side effects or severe pain refractory to medications. In such cases a number of surgical procedures may be performed, most of which are directed at the trigeminal nerve and/or nervus intermedius (geniculate systems). Destructive interventions which involve harming the petrosal nerve include radiofrequency rhizotomy and percutaneous glycerol rhizotomy, surgeries which are identical to those for trigeminal neuralgia (TN). Immediate relief is achieved in 50 to 70 percent of cases, while 10 to 30 per cent of cases achieve improved pain control.

Alternatively, microvascular decompression of the trigeminal nerve, with or without partial cutting of the nervus intermedius, offers a non-destructive surgical treatment for cluster headache. Approximately half of cluster headache sufferers attain good long-term control of their headache following this procedure.

Geniculate Neuralgia (GN)

Geniculate neuralgia (GN), also called nervus intermedius neuralgia, is a rare disorder that involves severe pain deep in the ear, which may spread to the ear canal, outer ear, mastoid, or eye regions. GN may also occur in combination with trigeminal (TN) or glossopharyngeal neuralgia (GPN).

The pain of GN is a sharp, shooting, or burning pain that can last for hours. Painful attacks can be triggered by cold, noise, swallowing, or touch, but triggers are typically quite unique to the sufferer. Other related symptoms that may be experienced include increased salivation, bitter taste, tinnitus, and vertigo. This disorder usually occurs in young to middle-aged adults and more commonly in women.

GN may be caused by neurovascular compression of the fifth, ninth and/or tenth cranial nerves. In sufferers of GN, signals sent along these nerves are altered and interpreted by the geniculate ganglion (a structure in the brain) as pain. GN which develops following herpes zoster oticus (Ramsey Hunt syndrome), where cold sores occur on the ear drum or ear, can also be associated with facial paresis (weakness), tinnitus, vertigo, and deafness.

Treatments: GN cannot typically be treated with medications. A variety of surgeries can be performed, including microvascular decompression (MVD) surgery of the fifth, ninth, and tenth nerves, as well as partial cutting of the nervus intermedius, geniculate ganglion, chorda tympani and/or the ninth and tenth cranial nerves.

Sphenopalatine Neuralgia

Also known as Sluder's neuralgia, this facial pain disorder is characterized by unilateral headache behind the eyes with pain in the upper jaw or soft palate, and occasional aching in the back of the nose, the teeth, the temple, the occiput, or the neck. The pain is associated with nasal and/or sinus congestion, swelling or redness of nasal mucous membranes, tearing, and redness of the face. Although Sluder's neuralgiaare and cluster headache are characterized by similar symptoms, Sluder's neuralgia involves pain that is longer in duration, with inflamed nasal mucosa on the involved side.

This disorder is twice as common in women as in men and appears to be caused by an irritation of the sphenopalatine ganglion from intranasal infection, deformity, or scarring.

Treatments: Medical therapy for sinus decongestion can alleviate symptoms. Ganglion blocks are also effective for pain control, either by intranasal application or direct injection. The underlying cause of Sluder's neuralgia, if apparent, can also be targeted.

Paratrigeminal Neuralgia of Raeder

This syndrome consists of headaches in the upper face associated with eye and skin changes (oculosympathetic palsy) on one side of the face. The pain is described as intense or throbbing, and there may also be drooping of the eyelid and contraction of the pupil (miosis). Symptoms are frequent in the morning, and attacks can last between a few days and a few weeks. Some sufferers experience an unpleasant taste (dysageusia), possibly due to involvement the chorda tympani (a branch of the VII cranial nerve).

Paratrigeminal neuralgia of Raeder is separated into two groups. Sufferers with symptomatic paratrigeminal neuralgia usually have parasellar cranial nerve defects, including tumours and lesions, and a neuropathic quality of pain. The migranous form with oclulosympathetic palsy is of unknown cause, but may be associated with upper respiratory infection, pneumonia, otitis media, chronic sinusitis, and dental abscess.

Anaesthesia Dolorosa

Following injury to the trigeminal nerve, a painful area of numbness may develop that is diagnosed as anesthesia dolorosa. This pain is severe and constant and described as burning, gnawing, or stinging. The most common cause is from destructive interventions for trigeminal neuralgia.

Treatments: Treatment of anaesthesia dolorosa is often ineffective, and medications will often not relieve the pain. Surgical interventions that have been tried, but yielding only limited success, include focused injury to the brain stem (tractotomy of the nucleus caudalis), deep brain stimulation, and pre-motor cortex stimulation. Other destructive interventions that have been attempted hae generall been ineffective.

Atypical Facial Pain

Atypical (or idiopathic) facial pain is characterized by deep, achy, constant, pulling, or crushing pain that involves diffuse areas of the face and head. The pain fluctuates in intensity and severity. No trigger points on the face can be found, and pain, which is often worse at night, may be aggravated by activity. In the majority of cases, only one side of the face is affected, but pain on both sides is also possible. Initial symptoms may appear similar to those of trigeminal neuralgia (TN), although they progress to an atypical facial pain pattern.

The diagnosis is made when the origin of pain is undetermined or when symptoms do not correlate with any other facial pain syndrome. Atypical facial pain, which affects more women than men, is often accompanied by depression. Nevertheless, this disorder is not of psychogenic origin.

Treatments: Unfortunately, atypical facial pain is usually difficult to treat, and surgery is generally avoided. While radiofrequency rhizotomy has been performed, such destructive interventions may actually worsen the pain. Tricyclic antidepressant medications can provide sufferers with modest relief of their symptoms. Conventional analgesic drugs, including opioids, can also be effective in selected individuals, often under the direction of a comprehensive pain management program.

Occipital Neuralgia

Occipital neuralgia is characterized by jabbing pain radiating from the neck to the back of the head on one side (distributions of the occipital nerve). The pain may also radiate to the forehead and eye, and there is usually some nerve tenderness and numbness in the affected area. There may be a continuous aching or throbbing pain upon which jabbing pains are superimposed. Attacks can be intensified or provoked by physical or emotional stress.

This disease is typically caused by acute or chronic trauma, entrapment, or inflammation at any point along the course of the C2 and C3 nerves. Many sufferers will have had a previous "whiplash" injury to the head, but lesions are not apparent in radiological imaging.

Other disorders may be confused with occipital neuralgia and include migraine or myofascial pain, C1-C2 arthroses, temporal arteritis, inflammatory disorders, post-herpetic neuralgia, occipital adenopathy and neurosyphillis. Occipital neuralgia is similar to glossopharyngeal, trigeminal, and geniculate neuralgias, but is differentiated according to the location of pain.

Treatments:Carbamazepine or Neurontin can reduce occipital neuralgia pain. Injections of local anesthetic (diagnostic blocks) may temporarily relieve occipital neuralgia. Repeated injections can be combined with steroids for longer lasting pain control in some individuals.

For severe and intractable pain, a variety of nerve injury procedures may be considered. These include C2 ganglionectomy by surgery or radiofrequency lesions, peripheral neurectomy, and intradural rhizotomy. As with all destructive interventions (rhizotomies) for neuralgic pain, long-term pain relief is not guaranteed and complications including weakness and numbness may occur.

Microvascular decompression of the C2 root and ganglion at the neural foramen has been described. A ventrolateral partial rhizotomy of the posterior rootlets of C1, C2 and C3 is a potentially curative procedure. Good long-term pain relief may be achieved with reduced risks of developing post-operative vertigo (dizziness), scalp anaesthesia (numbness), that are often encountered following non-selective rhizotomies. Another treatment option recently described is placement of an occipital nerve stimulator. This device is permanently implanted like a pacemaker and applies an electrical current to the occipital nerves that may result in continued pain relief.

Tinnitus and Vertigo

Disorders of the vestibular cochlear nerve (VIII) can result in tinnitus (ringing noise in the ear), vertigo (sensation of spinning), dizziness, nausea, or hearing loss. There are many possible causes for these various symptoms, which are generally investigated by specialists in Otolaryngology. In rare instances, neurovascular compression involving the vestibular cochlear nerve may be implicated as the cause of such symptoms. In such cases, microvascular decompression (MVD) surgery has been performed to cure patients of these symptoms.